mirror of
https://github.com/mutouyun/cpp-ipc.git
synced 2025-12-07 01:06:45 +08:00
67 lines
2.3 KiB
C++
67 lines
2.3 KiB
C++
/**
|
|
* \file libipc/memory_resource.h
|
|
* \author mutouyun (orz@orzz.org)
|
|
* \brief Implement memory allocation strategies that can be used by pmr::allocator.
|
|
*/
|
|
#pragma once
|
|
|
|
#include <type_traits>
|
|
#include <cstddef> // std::size_t, std::max_align_t
|
|
|
|
#include "libipc/imp/export.h"
|
|
#include "libipc/def.h"
|
|
|
|
namespace ipc {
|
|
namespace mem {
|
|
|
|
/// \brief Helper trait for memory resource.
|
|
|
|
template <typename T, typename = void>
|
|
struct has_allocate : std::false_type {};
|
|
|
|
template <typename T>
|
|
struct has_allocate<T,
|
|
typename std::enable_if<std::is_convertible<
|
|
decltype(std::declval<T &>().allocate(std::declval<std::size_t>(),
|
|
std::declval<std::size_t>())), void *
|
|
>::value>::type> : std::true_type {};
|
|
|
|
template <typename T, typename = void>
|
|
struct has_deallocate : std::false_type {};
|
|
|
|
template <typename T>
|
|
struct has_deallocate<T,
|
|
decltype(std::declval<T &>().deallocate(std::declval<void *>(),
|
|
std::declval<std::size_t>(),
|
|
std::declval<std::size_t>()))
|
|
> : std::true_type {};
|
|
|
|
template <typename T>
|
|
using verify_memory_resource =
|
|
std::enable_if_t<has_allocate <T>::value &&
|
|
has_deallocate<T>::value, bool>;
|
|
|
|
/**
|
|
* \class LIBIPC_EXPORT new_delete_resource
|
|
* \brief A memory resource that uses the
|
|
* standard memory allocation and deallocation interface to allocate memory.
|
|
* \see https://en.cppreference.com/w/cpp/memory/new_delete_resource
|
|
*/
|
|
class LIBIPC_EXPORT new_delete_resource {
|
|
public:
|
|
/// \brief Returns a pointer to a `new_delete_resource`.
|
|
static new_delete_resource *get() noexcept;
|
|
|
|
/// \brief Allocates storage with a size of at least bytes bytes, aligned to the specified alignment.
|
|
/// \remark Returns nullptr if storage of the requested size and alignment cannot be obtained.
|
|
/// \see https://en.cppreference.com/w/cpp/memory/memory_resource/do_allocate
|
|
void *allocate(std::size_t bytes, std::size_t alignment = alignof(std::max_align_t)) noexcept;
|
|
|
|
/// \brief Deallocates the storage pointed to by p.
|
|
/// \see https://en.cppreference.com/w/cpp/memory/memory_resource/deallocate
|
|
void deallocate(void *p, std::size_t bytes, std::size_t alignment = alignof(std::max_align_t)) noexcept;
|
|
};
|
|
|
|
} // namespace mem
|
|
} // namespace ipc
|